The present invention relates to a device for fixing a child seat to a support structure of a motor vehicle with a plastically deformable holding device, which is fixed to the support structure and has a holding element to which a fixing element, which is attached to the child seat, can be fixed.
The fixing element may be a fixing hook, which is attached to one end of a strap, the other end of which is fixed to the upper region of the child seat. The strap with the hook is also referred to as a Top Tether, which is used in the USA and Canada for fixing child seats to the vehicle structure.
German laid-open specification DE 198 00 072 A1 discloses a restraint system for a child seat, which is carried in a motor vehicle and is deposited on a seat of the motor vehicle. The child seat is provided with at least one integrated latching device which, during the fixing of the deposited child seat, enters into engagement with at least one fixing device attached to the seat or, in the vicinity thereof, to a body part of the motor vehicle and is fixed on the seat or vehicle. To improve the restraining capability of the latching or fixing device, at least one deformation element is arranged between the child seat and the seat or the body part, the deformation element plastically deforming when a predetermined force is exceeded, thereby permitting a limited forward movement of the child seat in relation to the vehicle seat in order to reduce a peak stressing of the latching and/or fixing device.
The German translation DE 695 11 954 T2 of European patent specification EP 0 689 955 B1 discloses a child seat fixing device, which contains an energy-absorbing plate member having a first tab and a second tab and a first edge and a second edge, which edges extend therebetween, and having a center portion which is substantially midway between the first and second tabs.
It is an object of the present invention to provide a device for fixing a child seat to a support structure of a motor vehicle, with a plastically deformable holding device, which is fixed to the support structure and has a holding element to which a fixing element, which is attached to the child seat, can be fixed. The fixing device permits a defined movement of the holding element during deformation of the holding device, and not just in the vehicle longitudinal direction.
This and other objects and advantages are achieved by the device according to the invention for fixing a child seat to a support structure of a motor vehicle, in which a plastically deformable holding device fixed to the support structure has a holding element to which a fixing element (attached to the child seat) can be fixed. The holding device has at least one bending axis, along which it can be deformed when a force, such as a tensile force, acts on it. In known child seat fixing devices, the holding element moves in the direction in which the force applied to the holding element acts, i.e., generally in the vehicle longitudinal direction. In child seat fixing devices according to the present invention, the bending axis permits a defined movement of the holding element, for example, on an arc of a circle.
In a further exemplary embodiment of the device, the bending axis is arranged transversely with respect to the vehicle longitudinal direction. The effect achieved by this is that the holding element moves on an arc of a circle when a tensile force is applied to the holding element.
In another exemplary embodiment of the device, the holding device has a plurality of bending axes, which are arranged transversely with respect to the vehicle longitudinal direction and are designed such that the holding device is successively deformed in a defined bending sequence along a particular bending axis when a force, such as a tensile force, acts on the holding element. By means of the bending sequence, kinematics can be predetermined for the holding element under load such that the holding element does not come to bear against the support structure when the holding device is deformed.
In another exemplary embodiment of the device, the holding device has a first bending axis, which, both in the undeformed and in the deformed state of the holding device, is arranged below the upper edge of the support structure. The holding device has a second bending axis, which, in the undeformed state of the holding device, is arranged below the upper edge of the support structure and below the first bending axis, and, in the deformed state, is arranged above the upper edge of the support structure. The distance between the bending axes may be greater than the distance of the first bending axis from the upper edge of the support structure. The effect achieved by the above-described structure is that, during deformation of the holding device, the holding element does not come to bear against the support structure.
In another exemplary embodiment of the device, the holding device has a fixing portion delimited by the first bending axis, a holding portion delimited by the second bending axis, and a lever portion arranged between the two bending axes. The fixing portion can have at least one through hole which serves to receive a fixing element, such as a screw. The holding portion and/or the lever portion can be provided with at least one cutout.
In another exemplary embodiment of the device, the holding device has a first bending axis delimiting a fixing portion, a second bending axis, and a third bending axis, delimiting a holding portion, wherein a respective lever portion is formed between the first and second bending axes and between the second and third bending axes. The three bending axes make it possible to significantly reduce the loading of the support structure.
In another exemplary embodiment of the device, the holding device is formed from a piece of plastically deformable sheet metal. Apertures and/or predetermined points of weakness may be provided in the sheet metal in order to restrict the level of force linearly, degressively or progressively.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.